Expansion valve with adjustable metering orifice



July 7, 1964 H. J. LONN 3,139,903

EXPANSION VALVE WITH ADJUSTABLE METERING ORIFICE Filed Feb. 21, 1961 E6010 jl 2 Sheets-Sheet 1 INVENTOR.

659E040 r]. Lou/v y 7, 1964 H. J. LONN 3,139,903

EXPANSION VALVE WITH ADJUSTABLE METERING ORIF'ICE Filed Feb. 21, 1961 2Sheets-Sheet 2 IN VENTOR.

L nea .0 I]; LON/V flrraeusys United States Patent 3,139,903 I EXPANSIONVALVE WITH ADJUSTABLE METERING ORIFICE Harold J. Lonn, Milwaukee, Wis.,assignor to International Telephone and Telegraph Corporation,Baltimore, Md.,

a corporation of Maryland Filed Feb. 21, 1961, Ser. No. 90,699 2 Claims.(Cl. 137-359) This invention relates to a valve structure and moreparticularly to an expansion valve useful in refrigerating systems.

Valves of this character are in quite common use. They open in responseto an increase in temperature at the place to be cooled for admittingvaporized refrigerant (such as Freon) into the expansion coil.

It is advantageous to predetermine the maximum rate of refrigerant flowto the coil to correspond to the capacity of the coil to utilize theexpanded refrigerant, or to predetermine the rate of flow to fit thecapacity of the compressor. This limiting rate of flow is accomplishedby providing a metering orifice in series with the valve port so thatthe liquid refrigerant passes from the orifice to the valve. In thepast, changes in the metering orifices have been difficult and usuallynecessitated at least a partial dismantling of the valve and aconsequent temporary shutdown of the system.

It is one of the objects of this invention to obviate such occurrencesand to make it possible to select an appropriate size metering aperturewithout at all dismantling the valve, and in a relatively simple andrapid manner.

Due to these features, it is possible temporarily to increase the rateof flow of refrigerant to produce immediate chilling of the expansioncoil, and yet without danger of overloading the compressor.

This invention possesses many other advantages and has other objectswhich may be made more clearly apparent from a consideration of oneembodiment of the invention. For this purpose, there is shown a form inthe drawings accompanying and forming a part of the presentspecification. This form will now be described in detail, illustratingthe general principles of the invention; but it is to be understood thatthis detailed description is not to be taken in a limiting sense, sincethe scope of this invention is best defined by the appended claims.

Referring to the drawings:

FIGURE 1 is a longitudinal cross-sectional view of a valve structureincorporating the invention;

FIG. 2 is a fragmentary sectional view, taken along a planecorresponding to line 2-2 of FIG. 1; I

FIG. 3 is a fragmentary end view of a portion of the valve structureshown in FIG. 1;

FIG. 4 is a sectional view, taken along a plane corresponding to line4-4 of FIG. 1; and

FIGS. 5 and 6 are fragmentary sectional views, similar to FIG. 4, ofmodified forms of the invention.

In the form shown in FIGS. 1 to 4, the valve structure is utilized as anexpansion valve for refrigerants, such as Freon.

Thus, the valve structure includes a main body 1 having a generallycylindrical portion 2 forming an expansion space 3.

In the present instance, a lateral extension 4 provides an inlet opening5. A similar lateral extension 6, leading from the expansion chamber 3,is formed integrally with the valve body 1 and serves as an outlet. Thisoutlet 6 may be appropriately connected to the inlet side of anexpansion coil.

A conical-shaped wire screen 7 may be inserted into the opening 5 forseparating foreign matter from the incoming fluid.

3,139,903 Patented July 7, 1964 The inlet opening 5 has an enlargedportion 8 which, together with opening 5, provides an opening extendinglaterally entirely across the body 1. Its left-hand end is closed by agland nut 9 threaded into the left-hand end of the enlarged portion 8.This gland nut will be further referred to hereinafter.

The flow of refrigerant passes toward the left through inlet 5, asviewed in FIG. 1, thence downwardly through a metering aperture 10,through a valve seat member 11, into the expansion chamber 3, past aball closure 12. The valve seat member 11 may be fastened in anappropriate opening 13 extending from the opening 8' downwardly into theexpansion chamber 3.

This ball closure 12 is automatically opened in response to arequirement for additional refrigerant in the expansion coil of thesystem. Since such uses of the expansion valve are now well-known,further description thereof is unnecessary.

The ball closure 12 is mounted in the upper face of a disc 14 in anyappropriate manner. For example, the ball 12 may be held in place by theaid of an upset flange 12a formed on the upper side of the disc 14.

The disc 14 has a central, downwardly directed boss 15 serving as aguide for the upper end of a compression spring 16 which urges theball12 to closing position.

The lower end of the spring 16 is similarly guided by a boss 17 mountedon a disc 18. This disc 18 is internally threaded for the reception ofan adjusting screw 19. This screw 19 is provided with a collar 20integral with a cylindrical extension or stem 21. The collar 20 restsupon a shoulder 22 formed by the aid of a counterbore of the opening 23.This opening rotatably accommodates the cylindrical extension 21.

The aperture 23 is formed in a fitting 24 having a hollow, upwardlyextending, externally threaded portion 25. This extension 25 is threadedinto the lower end of the body portion 2. The fitting 24 has aknife-edge flange 26 which serves to seal 011 the body member 2. Theperiphery of fitting 24 is hexagonal to make it possible to manipulatethe fitting 24 by the aid of a wrench.

The screw 19 can be rotated to adjust the force exerted by thecompression spring 16. For this purpose, the stem 21 is provided at itsend with a non-circular portion 27 by the aid of which the stem 21 maybe turned.

The stem 21 is sealed off by the aid of a resilient packing 28surrounding the stem 21. This packing 28 is urged into sealingrelationship by the aid of a packing gland nut 29 threaded into athreaded opening 30 provided in the fitting 24.

In order to enclose the end 27, a cap 31 is threaded on exterior threadsformed on the fitting 24. A knifeedge flange 32, located on the fitting24, seals against the upper edge of the cap 31.

When conditions require it, the disc 14 is urged downwardly against theforce of the spring 16 so as to unseat the ball 12 to the position shownin FIG. 1. The mechanism for accomplishing this is illustrated in FIG.2.

Thus, a pair of thrust pins 33 are mounted for vertical movement in thebody 1. The lower ends contact the disc 14. These thrust pins 33 arecarried by a disc 34 guided by an extension 35 formed on the body 1.

The disc 34 is urged downwardly by fluid pressure in a A central boss 41serves to accommodate a conduit 42 leading to a slanting port 43. Thisslanting port is in communication with the chamber 36. The conduit 42 isin communication with a device sensing temperature, such as a pressurecell or bulb 44. This pressure cell or bulb is located in the space tobe refrigerated. Upon an increase in temperature, the bulb 44 causes avolatile filling to expand and to exert fluid pressure in the chamber36. When the temperature reaches a sufficiently high level, the pushpins 33 are operated to depress the ball 12 from its seat 11, therebyopening the valve.

A sheet metal name plate 45 may be disposed, if desired, over the covermember 38.

The size of the metering orifice determines the level of maximum fiow ofthe refrigerant to the expansion coil. It is desirable at times to makeit possible to select a proper sized metering orifice to correspond tothe desired maximum flow.

In the past, this has been accomplished by providing removable elementsin the mechanism and replacing them to define different sized orifices,as required. This necessitated a dismantling-of the apparatus.

In the present instance, the size of the metering orifice can beadjusted externally of the apparatus simply by turning a stem 46. Thisstem 46 extends into the inlet opening 8, and integrally carries at itsright-hand end a hollow cylinder 47.

This hollow cylinder, as shown most clearly in FIG. 2, has equiangularlyspaced orifices 10, 10a, 10b and 100 of different sizes. Accordingly, byrotating the stem 46, it is possible to cause alignment of the selectedorifice with the port extending through the valve seat 11.

To facilitate adjustment, the left-hand end of the stem 46 is flattened,as indicated in FIG. 3, to enable it to be readily turned by the aid ofa wrench. Furthermore, indicia 48 may be marked on the head 49 of thegland nut 9. This indicia is intended to cooperate with an arrow 51marked on the end surface of the stem 46.

In order properly to seal off the stem 46, use is made of a sealing ring52 around the stem 46. This ring may be of rubber, such as an 'O-ring. Awasher 53 may be interposed between the packing ring 52, and theshoulder formed by the left-hand surface of cylinder 47.

A packing gland 54 is urged against the right-hand edge of the cylinder47. This packing gland is provided with a hub portion 55 definingashoulder against which another resilient sealing or packing ring 56 maybe urged. Adjacent this packing ring 56 is a hollow sight glass 57 (seealso FIG. 4) which may be viewed through an opening 58 in the body 1.

Adjacent the right-hand end of the sight glass 57 is another packinggland 59 similar to packing gland 54. This packing gland 59 is alsoprovided with a resilient packing or sealing ring 60. This sealing ringis urged toward the left by the aid of a compression spring 61. Theright-hand end of this spring 61 abuts a shoulder 62 formed between theopenings 5 and 8 which constitute the inlet to the valve.

By the aid of the compression spring 61, the packing or sealing rings52, 56 and 60 are placed under compression so as to prevent egress ofrefrigerant to the exterior of the valve.

In the form shown in FIG. 5, the sight glass 57, as before, is urgedagainst the packing gland 54. This packing gland does not directlycontact the hollow cylinder structure 63. Instead, the packing gland 54-rests on the shoulder 64 defined by the aperture 65 of smaller diameterthan the aperture 8.

The hollow cylinder 63, similar to hollow cylinder 47, bottoms on theshoulder formed between the aperture 66 and the aperture 65. The stem 67is capable of angular adjustment as before. It is sealed by the aid of aresilient packing collar or ring 68 urged into packing relation by theaid of a gland nut 69.

In the form shown in FIG. 6, the sight glass is omitted. Instead, thegland 54 is urged inwardly against the righthand edge of the hollowcylinder 47 by the aid of compression spring 70.

The capability of adjusting the size of the metering orifice isadvantageous temporarily to increase or decrease the rate of fiow ofrefrigerant to the expansion coil. Thus, the size of the meteringorifice may be decreased in the event that it is desired to start thesystem from a warm condition. Under such circumstances, quick coolingcan be effected without overloading the compressor. After sufficientcooling has been effected, the orifice size may be readily increased tothat desired.

, between an intermediate portion of said inlet opening and the outletopening, said passage including a port; a rotary hollow cylinder guidedin said inlet opening and overlying said port; said cylinder havingangularly spaced openings optionally registrable with the port to form ametering orifice; the interior of the cylinder being in communicationwith the inlet opening; a stern for the cylinder extending out of thebody and rotatable to adjust the cylinder for registering any one ofsaid angularly spaced openings with the port; one end of said cylinderforming an annular shoulder around the stem; a resilient sealing ringdisposed on the shoulder; a packing nut around the stem and forming anabutment for the ring; a packing gland engaging that end of the cylinderopposite the stem; a resilient sealing ring adjacent the side of thegland opposite the cylinder; means resiliently urging the packing glandagainst the cylinder; a sight glass interposed between hte resilienturging means and the packing gland; and sealing means between the sightglass and the resiliently urging means.

2. In a valve structure: a valve body having an inlet opening and anoutlet opening; said inlet opening extending entirely through the valvebody; there being a passage between an intermediate portion of saidinlet opening and the outlet opening, said passage including a port; arotary hollow cylinder guided in said inlet opening and overlying saidport; said cyinder having angularly spaced openings optionallyregistrable with the port to form a metering orifice; the interior ofthe cylinder being in communication with the inlet opening; a stem forthe cylinder extending out of the body and rotatable to adjust thecylinder for registering any one of said angularly spaced openings withthe port; one end of said cylinder forming an annular shoulder aroundthe stem; a resilient sealing ring disposed on the shoulder; a packingnut around the stem and forming an abutment for the ring; a firstpacking gland engaging that end of the cylinder opposite the stem; aresilient sealing ring adjacent the side of the gland opposite thecylinder; means resiliently urging the first packing gland against thecylinder; a sight glass interposed between the resiliently urging meansand the first packing gland; a second packing gland interposed betweenthe sight glass and the resiliently urging means; and a resilientsealing ring around the said second packing gland.

References Cited in the file of this patent UNITED STATES PATENTS967,009 Frishmuth Aug. 9, 1910 1,088,103 Schreidt Feb. 24, 19141,393,615 Foltz Oct. 11, 1921 1,887,235 Cornelius Nov. 8, 1932 2,062,896Martocello Dec. 1, 1936 2,101,356 Zak Dec. 7, 1937 2,524,569 MattesonOct. 3, 1950 2,570,322 Christopher Oct. 9, 1951 2,743,552 Hunter May 1,1956 2,899,980 Loebel Aug. 18, 1959 2,973,325 Barrows Feb. 28, 1961

1. IN A VALVE STRUCTURE: A VALVE BODY HAVING AN INLET OPENING AND ANOUTLET OPENING; SAID INLET OPENING EXTENDING ENTIRELY THROUGH THE VALVEBODY; THERE BEING A PASSAGE BETWEEN AN INTERMEDIATE PORTION OF SAIDINLET OPENING AND THE OUTLET OPENING, SAID PASSAGE INCLUDING A PORT; AROTARY HOLLOW CYLINDER GUIDED IN SAID INLET OPENING AND OVERLYING SAIDPORT; SAID CYLINDER HAVING ANGULARLY SPACED OPENINGS OPTIONALLYREGISTRABLE WITH THE PORT TO FORM A METERING ORIFICE; THE INTERIOR OFTHE CYLINDER BEING IN COMMUNICATION WITH THE INLET OPENING; A STEM FORTHE CYLINDER EXTENDING OUT OF THE BODY AND ROTATABLE TO ADJUST THECYLINDER FOR REGISTERING ANY ONE OF SAID ANGULARLY SPACED OPENINGS WITHTHE PORT; ONE END OF SAID CYLINDER FORMING AN ANNULAR SHOULDER AROUNDTHE STEM; A RESILIENT SEALING RING DISPOSED ON THE SHOULDER; A PACKINGNUT